Molecular Mechanisms of Induction of Tolerant and Tolerogenic Intestinal Dendritic Cells in Mice

J Immunol Res. 2016:2016:1958650. doi: 10.1155/2016/1958650. Epub 2016 Feb 11.

Abstract

How does the host manage to tolerate its own intestinal microbiota? A simple question leading to complicated answers. In order to maintain balanced immune responses in the intestine, the host immune system must tolerate commensal bacteria in the gut while it has to simultaneously keep the ability to fight pathogens and to clear infections. If this tender equilibrium is disturbed, severe chronic inflammatory reactions can result. Tolerogenic intestinal dendritic cells fulfil a crucial role in balancing immune responses and therefore creating homeostatic conditions and preventing from uncontrolled inflammation. Although several dendritic cell subsets have already been characterized to play a pivotal role in this process, less is known about definite molecular mechanisms of how intestinal dendritic cells are converted into tolerogenic ones. Here we review how gut commensal bacteria interact with intestinal dendritic cells and why this bacteria-host cell interaction is crucial for induction of dendritic cell tolerance in the intestine. Hereby, different commensal bacteria can have distinct effects on the phenotype of intestinal dendritic cells and these effects are mainly mediated by impacting toll-like receptor signalling in dendritic cells.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Dendritic Cells / immunology*
  • Gastrointestinal Microbiome / immunology
  • Gastrointestinal Microbiome / physiology*
  • Homeostasis
  • Immune Tolerance*
  • Inflammation
  • Inflammatory Bowel Diseases / immunology
  • Inflammatory Bowel Diseases / therapy
  • Intestinal Mucosa / cytology
  • Intestinal Mucosa / immunology*
  • Intestines / immunology
  • Intestines / microbiology*
  • Mice
  • Phenotype
  • Signal Transduction / genetics
  • Signal Transduction / immunology
  • Symbiosis
  • Toll-Like Receptors / genetics
  • Toll-Like Receptors / immunology

Substances

  • Toll-Like Receptors